This invention relates to power line monitors, and more particularly to an improved system for monitoring the power supply to computers, or the like. Even more particularly, this invention relates a combined power line monitor and printer system which senses and records voltage variations which would deleteriously effect computer operations.
Heretofore a variety of devices have been developed and utilized for monitoring the voltage supply to computers and the like. U.S. Pat. No. 4,600,962, for example, discloses a monitoring system which includes a sensing circuit for detecting undesirable changes in the power supply to computers, together with associated alarm and timing circuits. The disadvantage of this type of system, however, is that it is extremely complicated, and does not supply a hard copy printout of the sensed errors. U.S. Pat. No. 3,950,759 also denotes a monitoring system, but it is particularly designed for use with a welding unit; and although it does provide a hard copy printout of current and voltage variations, it is not adaptable to monitoring power supplies for lower DC power operated units such as computers and the like.
U.S. Pat. Nos. 4,586,104 and No. 4,470,041 also disclose monitoring circuits for computers and the like, but neither is designed to provide a hard copy printout or record of the sensed errors. Moreover, in none of the above-noted systems is there disclosed a stand-alone monitor or sensor in combination with a separate printer, the input of which optionally can be connected to the output of the sensor module.
It is an object of this invention, therefore, to provide an improved power supply monitoring system which is particularly suited for use in connection with computers, and which utilizes an improved sensor and printer combination to produce a hard copy record of the various power supply faults detected by the sensor.
Still a further object of this invention is to provide an improved monitoring system of the type described in which a fault monitor and printer are coupled together to provide a continuous, hard copy record of the faults sensed by the monitor.
Another object of this invention is to provide a novel control circuit for selectively coupling a fault-sensing monitor to a line printer to enable operation of the monitor with or without the printer.
A further object of this invention is to provide an improved power supply monitoring system of the type described which continuously produces in multi-track form a hard copy record of each detected fault and the time at which a respective fault occurred.
Other objects of this invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with accompanying drawings.